VirtualBox aborts when I power off VM

[BigPopper]

I'm running OS X Mohave (10.14.3) on a 16GB Macbook Pro (Intel Core i7), and using the latest Version of VirtualBox (6.0.4). I have a Windows 8.1 VM that has been working just fine for several years, but I recently installed a Windows XP (sp3) and a Centos7 VM. Both have 2GB of RAM and are both Bridged Network, 1 core. Both VMs run great when they run, but when I power them down, I see a quick "power off" message, then VirtualBox aborts. Then I get a message that VB closed unexpectedly, ignore, report, or reopen? The next time I load VBox, the machines seem fine - no damage or corruption. But it aborts 100% of the time I power off the machines, while my 8.1 machine is just fine. I've experimented with various video settings, but nothing changes. It seems like if this were a bug, it would be reported already - so I'm convinced it's something I've done wrong, but I've tried so many settings, I don't know what else to try. Any ideas?

[socratis]

Moving to "OSX Hosts" from "Using VirtualBox".
I'm pretty sure that this sounds awfully familiar, but a 30" search didn't find anything. Maybe it was in the bugtracker(?), I'll keep on looking...

We need to see a complete VBox.log, from a complete VM run, where the problem occurs:

• Start the VM from cold-boot (not from a paused or saved state) / Observe problem / Try to close the VM.
• With the VM and VirtualBox aborted, relaunch VirtualBox, right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response. See the "Upload attachment" tab below the reply form.

Also, I need to see the output of the following command in the Terminal:

• kextstat | grep -v com.apple